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What's Kotlin strategy for dropping support for older `languageVersion`? Looks like 2.3 drops support for `languageVersion &lt; 1.9` ? It's a ~2.5 years window which means I can't use KGP 2.3 and target Gradle 8, which is still widely in use.
I'm not asking that we have a 12 years java8-like update window but a couple more years would be useful. Or is this made on purpose to drive the ecosystem forward?

You can use KGP 2.3 but switch compiler version via BTA: <https://kotlinlang.org/docs/build-tools-api.html|https://kotlinlang.org/docs/build-tools-api.html>


"the three last major versions" so that's ~2 years indeed

And as stated in <https://kotlinlang.org/docs/kotlin-evolution-principles.html#compatibility-options|https://kotlinlang.org/docs/kotlin-evolution-principles.html#compatibility-options> compiler supports 3 previous versions

Any chance to have that bumped a little bit?

In Dokka, for example, we still support Gradle 7, by using 2.0.21 compiler and KGP 2.3 :)

And language version 1.something (don't remember)

KGP is the main thing I need really up to date

kotlinc would be nice as well but can probably work with older versions

<https://github.com/pschichtel/tiny-jib/pull/6/changes/f380a2cb697b8d2303140e77efd8d2c725fc76cf|That worked>

Somewhat of a rant but:
```kotlin.compiler.runViaBuildToolsApi```
why do I need a Gradle property in addition to the experimental API?

My `gradle.properties` file is a graveyard of experimental flags. I wish everything was a Kotlin API where the lifecycle can be managed

&gt; why do I need a Gradle property in addition to the experimental API?
My guess: to enable *experimental* BTA usage without changing the compiler version.
For a more official answer, I will summon <@U58GRE73J>. :kodee-floating:

P.S. I've checked Dokka, and we do compile with AV/LV 1.4, Kotlin compiler 2.0.21, and KGP 2.3 (<https://github.com/Kotlin/dokka/blob/master/gradle/libs.versions.toml#L3-L10|source>).

Thanks!
Also again completely sidetracking this discussion but how did you land on 1.4? Is there a published distribution of Gradle versions used by Kotlin developers somewhere? That could be handy to decide what version of Gradle to support. I usually do Gradle 8+ these days but I must say this isn't really backed by actual data.

&gt; how did you land on 1.4?
That's pretty easy:
• Even for the latest KGP (2.3.0), the minimum supported Gradle version is 7.6. (<https://kotlinlang.org/docs/gradle-configure-project.html#apply-the-plugin|source>)
• Gradle 7.6 uses LV 1.4. (<https://docs.gradle.org/current/userguide/compatibility.html#kotlin|source>)
• Dokka should be compatible with all the same versions as KGP.
Previously, there was one more requirement: we had a build of stdlib documentation for older versions (like really old: 1.0 and up), which required us to support even older Gradle versions.

P.S. DGPv1 currently <https://github.com/Kotlin/dokka/blob/3cfe07f356388160474867d431a752fee95585d9/dokka-runners/dokka-gradle-plugin/src/classicMain/kotlin/DokkaClassicPlugin.kt#L24|checks> that we have at least Gradle 5.6, though, with Dokka 2.0.0, we support only 7.6 there, as we dropped support for Gradle 6.x in <https://github.com/Kotlin/dokka/pull/4189|this pr>. And yes, for a while we had IT tests running on older Gradle versions! Compatibility in Dokka is a long and complicated story.

JiC: again - take a look into Kotlin Build Tools API and it's ability to use older Kotlin compiler version in a modern KGP: <https://kotlinlang.org/docs/build-tools-api.html#compatible-kotlin-compiler-and-kgp-versions>

Yep, I just did and <https://kotlinlang.slack.com/archives/C8C4JTXR7/p1771419511835239?thread_ts=1771406980.040849&amp;cid=C8C4JTXR7|it worked>!